It has been reported that ADD and/or ADHD are developmental disorders that consists of attention span, impulse control and self-control. It has been reported that though the pathogenesis of ADD and/or ADHD has not been fully investigated, it is known that traditionally, methylphenidate has been used in the treatment of ADD and/or ADHD for both children and adults. It is also known that methylphenidate can also be used in the treatment of diseases including but not limited to postural orthostatic tachycardia syndrome and narcolepsy.
Daytrana® (methylphenidate transdermal system) is available in four dosage strengths (10, 15, 20 and 30 mg/day) and is applied for 9 hours using patch sizes correlated with the dose (12.5, 18.75, 25 and 37.5 cm2, respectively). Daytrana® is a polymer matrix comprising an acrylic pressure-sensitive adhesive. However, the peel force from the release liner of the patch increases over time. This creates a serious issue as patients may encounter difficulties or unable to remove the release liner for use. In addition, it has been reported that currently available methylphenidate patches have leaking issues where the methylphenidate leaks out of the patch. This also creates a problem where the large size patches are too soft to handle. This problem is more severe if the methylphenidate patches are stored for several months or longer. See US20140271792 A1, US 2016/0030362 A1 and NDA 21-514 CMC review. In addition, currently available methylphenidate patches have low permeation and flux rate (˜9.1 μg/cm2 hr see US 2016/0030362 A1). As methylphenidate will cause skin sensitization (Daytrana® package insert, Cheng C. J of Pediatrics January 2017 Vol 180, P 241-246), when compensate for the low permeation rate, larger patches are needed, i.e. 37.5 cm2.
Therefore, there is a need to develop an optimal methylphenidate formulation with high flux to reduce drug loading and patch size to minimize the skin sensitization and exhibit suitable physical and pharmacokinetic properties. The presently disclosed transdermal delivery system has a higher permeation and flux rate than previously known methylphenidate transdermal delivery system in the market. Because of these improved properties, the same or more of the active pharmaceutical agents can be delivered. The patches of the present disclosure do not have the currently undesirable issues for being leaky, too soft to handle and too large to be comfortably applied to a patient. The presently disclosed methylphenidate transdermal delivery system improves the quality of life of caregivers and patients who are suffering from ADD and/or ADHD, postural orthostatic tachycardia syndrome and narcolepsy (Findling R, Dinh S, CNS Drugs (2014) 28:217-228).